While many collectors acquire guitars
and amplifiers, Tony Bruno
is constantly on the search for capacitors
and resistors, both new-old-stock (NOS)
and modern. Bruno keeps a library of
these parts in the upstate New York shop
where they become the guts of some of the
most coveted boutique tube amps in the
world today. Some of these amps—like the
Underground 30, a mid-powered machine,
and the Cow Tipper Pro II 22, a 22-watt,
6V6 blackface Fender-inspired model—
have already become legend. Bruno’s reputation
even led to a gig working with Vox
on the design of new amps.

Bruno’s latest offering under his own
name is the Underground Custom, an
evolution of the Underground 30 that
incorporates different capacitors and resistors,
adds a Mid control, and includes
a negative feedback loop that re-voices
the amp significantly. The amp is the
product of Bruno’s restless need to refine
his work, and that drive has won over
more than a few high-profile guitarists.
One of Bruno’s most prominent fans is
country superstar Brad Paisley, who set
aside his beloved Trainwreck in favor of
a new Underground for recording the
leads on his forthcoming album, This is
Country Music. Given this endorsement
and Bruno’s work to date, we were super-psyched
to review the amp.

Gorgeous and Stone Solid
The Underground Custom is one handsome
amp. Our review model arrived clad in
black vinyl (though the amp can be ordered
in a variety of coverings), which contrasts
nicely with its silver grille and white vintage-style
chicken-head knobs. The Bruno also
manages to combine Fender, Vox, and old
Marshall styling cues without looking derivative.
On the grille you’ll find an especially
tasteful flourish, a simple Bruno logo in
an art deco–style font that underscores the
amp’s vintage aura and classy, upmarket feel.

Bruno spared little expense in building
the impressively solid Underground
Custom. The head’s chassis is made from
heavy-duty steel and the cabinet is constructed
from finger-jointed solid pine and
13-ply Baltic birch baffles, which discourage
rattling and unwanted vibration. Both
the head and cabinet have thick, padded
handles for comfortable hauling.

Inside the Underground Custom, the
handwired, point-to-point circuitry incorporates
CTS pots and other high-end electronics.
The tube sockets are made of ceramic, and
everything is held together with stainless-steel
screws and bolts.

The non-master-volume Underground
Custom has a somewhat unconventional tube
configuration—five EL84s and four 12AX7s.
However, that extra EL84 isn’t for power, it’s
a reverb driver. Like the Underground 30, the
Custom features about 36 watts of class-A
power. But unlike its predecessor, the Custom
has a solid-state rectifier in place of a GZ34.

The Custom’s front panel is elegant and
simple. At the far left is a single 1/4" input,
followed by three controls for the built-in
reverb—Mix, Tone, and Dwell—that will
be familiar to anyone who has used a standalone
Fender Reverb unit. To the right of
the reverb controls are the amp’s Treble,
Mid, Bass, and Presence knobs, followed by
a pilot light and the standard standby and
on-off toggle switches, plus a ground switch.
On the back of the amp are 1/4" outs for
8Ω and 16Ω speaker configurations.

Positively Killer Sounds
I auditioned the Underground Custom head
with a half-open Bruno cab equipped with
two 12" Celestion G12-65 speakers. Plugging
a recent Gibson 1963 ES-335 Historic with
factory Burstbuckers directly into the Custom,
I was blown away by the amp’s power. Set on
2, it seemed as loud as other 30-watt models
do at much higher volume settings.

Bruno says he conceived and voiced the
Custom for lead playing. So I first tried
some single-note lines in a variety of idioms,
including blues-rock and modal jazz.
The Custom did indeed impress in all these
contexts, delivering a warm and spongy
sound filled with blooming harmonics and
uncommon definition and sustain.

Adam Perlmutter is a freelance writer, transcriber, and engraver living in Culver City, California. He contributes to Premier Guitar, Acoustic Guitar, Guitar Aficionado, and other music magazines, and has written a number of instructional books, including Color Your Chords (Cherry Lane) and Jim Hall: Signature Licks (Hal Leonard).

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